Dear Ole Mechanic;

With fuel prices going through the roof, I have been hearing about “biodiesel”.  What the heck is it?  Is it any cheaper than regular diesel fuel?  Will it hurt my Dodge diesel?  Where can I get “biodiesel?"  I guess this is a bunch of questions, so what can you tell me about “bio diesel”?  

Thanks  Diesel Dodge Pickup 

Dear Diesel;Biodiesel Logo

I will hit the most important question first.  No, Biodiesel will not hurt the Cummins engine in your Dodge truck.  You see when Rudolph Diesel, yes he was a real person, patented the Diesel engine back in about 1893, it was to make use of vegetable oils as a fuel.  We had not figured out what all we could do with mineral oil yet.  Mineral oil is more commonly known as petroleum or crude oil.  Anyway, the Diesel engine was originally developed to use vegetable oil.  You know-- corn oil, peanut oil, sunflower oil, soybean oil and all kinds of vegetable oil.  As crude oil came into more use, it became the fuel for Diesel engines.  Now that crude oil prices are going through the roof, the renewable sources of vegetable oil are looking much better.  They were more expensive to refine than crude oil.  They WERE more expensive, but with the price of crude now - - -.  Vegetable oil is getting a lot closer in price.

That brings me to your first question “What the heck is it?”  Biodiesel is a blend of mineral oil (petroleum) and vegetable oil.  Normally it is called Biodiesel 10 or Biodiesel 20.  The number refers to the percent of vegetable oil mixed in with regular diesel fuel, so Biodiesel 10 means that the fuel is 90 percent diesel fuel and 10 percent vegetable oil.  In short the vegetable oil is being used to stretch the existing supply of diesel fuel by 10 or 20 percent.

Is it cheaper than regular diesel fuel?  Well it wasn’t, but the way fuel prices have been going up, it should be getting very close in price, plus the vegetable oil is produced here in the US and is not controlled by some other country.  Also, since the production of Biodiesel is just getting going good, it may be priced higher because true mass production and its cheaper costs have not really kicked in yet.

Your last question, “Where can I get “biodiesel”?” is a good one, but it is one that I can not answer.  I don’t know of any place locally that carries it.  You could try contacting one of the bulk distributors in Fredericksburg or Kerrville.

With that explanation of Biodiesel, you might wonder if you could burn 100 percent vegetable oil in your Dodge.  Yes, you can, but tests are still being conducted to see if there are any wear problems with long-term use.  You see, diesel injectors and pumps have been designed to use mineral oil over the past many years, and vegetable oil may not lubricate things quite the same.  This could cause the injectors or pumps to wear out too fast, and they are not cheap.  Only long-term tests will tell.  Could you go into a grocery store, buy cooking oil and dump it in your fuel tank?  Yes, but don’t let the Feds get wind of it, because you would not be paying the road-use tax that is included in the price of the fuel that you buy at filling stations.  Also, hope that the weather does not turn cold.  The cloud point of vegetable oil, that is the temperature at which it starts to congeal and get lumpy, is much warmer than regular diesel fuel.  Cold weather will cause it to congeal, plug up the fuel filter and shut your truck down untill the temperature warms back up.

Biodiesel sure sounds like a good idea.  A farmer could grow his or her own fuel and not need to worry about the price of crude oil.  We would just need to get accustomed to exhaust fumes that smell like French fries.

Herr Professor Nuzanbolts